Between 1968 and 1984, a 7272-yr oak chronology was constructed in Belfast, Northern Ireland, in order to provide a local calibration of the radiocarbon timescale. This single-minded exercise in chronology construction provided an exciting occupation for a group of researchers that can be likened to a race in which there was no guarantee of a finish. The existence of a parallel dendrochronological enterprise in Germany added both competition and the possibility of independent replication. The initial completion of both chronologies by 1984, and respective calibrations by 1986, left an important legacy of 2 absolutely dated tree-ring chronologies for multifarious research purposes.

The field of dendrochronology had a developmental “head start” of at least several decades relative to the inception of radiocarbon dating in the late 1940s, but that evolution was sufficiently advanced so that unique capabilities of tree-ring science could assure success of the 14C enterprise. The Laboratory of Tree-Ring Research (LTRR) at the University of Arizona played a central role in the cross-pollination of these disciplines by providing the first wood samples of exactly known age for the early testing and establishment of the “Curve of Knowns” by Willard Libby. From the 1950s into the early 1980s, LTRR continued to contribute dated wood samples (bristlecone pine and other wood species) to 14C research and development, including the discovery and characterization of de Vries/Suess “wiggles,” calibration of the 14C timescale, and a variety of tests to understand the natural variability of 14C and to refine sample treatment for maximum accuracy. The long and varied relationship of LTRR with 14C initiatives has continued with LTRR contributions to high-resolution studies through the 1990s and systematic efforts now underway that may eventually extend the bristlecone pine chronology back beyond its beginning 8836 yr ago as of 2009. This relationship has been mutualistic such that a half-century ago the visibility and stature of LTRR and dendrochronology were also elevated through their association with 14C-allied “hard sciences.”